Based on Mordecai Richler’s novel “Barney’s Version,” the film adaptation is a rich, meticulous character study fulfilled by an outstanding, award-caliber performance by the superb actor Paul Giamatti. The film unfolds with the literary dimension of a novel under the direction of Richard J. Lewis from a screenplay by Michael Konyves. It is one of the year’s superior screen achievements.

Giamatti plays Barney Panofsky, a quirky, larger-than-life Montreal Jew who has the instincts of a rebel, can be extremely funny but also leads a self-destructive life as a result of his impulsive behavior. After experiences in Italy in the 1970s, he comes back to Montreal and becomes a TV producer. The offbeat title of his company is Totally Unnecessary Productions.

The film follows the trajectory of his professional and romantic life. His first marriage to Clara (Rachelle Lefevre) ends tragically. His second wife, from a well-heeled family, is played by Minnie Driver, who becomes exasperated with his philandering and general behavior. On their wedding night he already pursues the charming, independent-minded Miriam, exquisitely played by Rosamond Pike, who at first brushes him off, but later succumbs to his incessant pursuit and marries him. Barney really loves Miriam, but given his self-destructive path, the liaison is also headed for trouble.

Barney’s ex-cop father, who can be gruff and tough, but is ever-loving toward his son, is played by Dustin Hoffman, a sure-fire scene stealer here. It is one of Hoffman’s especially colorful roles, and he makes the most of it, probably making him a supporting actor awards contender. Another key and showy role in the film, the drug-hooked, failed novelist Boogie, is played impressively by Scott Speedman. He is Barney’s long-time buddy, and mystery envelops the film as Boogie disappears after an emotional and physical clash between him and Barney in an eruption of bottled-up resentment.

For all of the humor, effervescence and drama in the film, the difficult Barney’s fate becomes a sad one, undercutting who he is and who he has wanted to be. The plot ultimately demonstrates that forces beyond our control can have the last word. Through it all Giamatti gives an astonishingly accomplished performance.